Not all edge lit number displays use flat plates for their display faces. This unusual device, a IND-1803 'Numerik Indicator' made by KGM, uses curved plastic plates to bend incoming light around a 90 degree turn before reaching the digit display area. This allows the display's incandescent lamps to be conveniently mounted on the rear of the device instead of the top and bottom faces as in many other edge lit displays. In the photo the display's cover has been removed and colored LED's have been used to show the light-bending plates in action. Instead of decimal points, this display makes use of a pair of left and right-centered dots which can act as either a decimal point or a colon separator depending on need. This display is designed to be mated to a special matching socket; the spring loaded clips mounted on the top and bottom of the display hold it in place when it is inserted into it's socket.

One of the most famous uses of this model of display was as the 3 digit bomb countdown timer shown in the James Bond movie Goldfinger. Even Bond villains lose patience trying to find enough of these to make a 6 digit clock.

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KGM IND-1803 'Numerik Indicator' edge-lit display, operation with LEDs. Note that the cover has been removed to allow viewing of the display's internal structure.

The General Radio IND-1803 makes use of unusual curved digit plates that direct the light from rear-mounted lamps.

The IND-1803 is designed to be mated to a matching socket that contains spring loaded contacts for the display's twelve incandescent bulbs.

IND-1803 Numerik Indicator driver module.

The IND-1818 is an edge lit overflow display with only four display plates. Characters displayed are 0, 1, +, and -.

Strangely, the official General Radio indicator driver module for the IND-1818 is as complex as the 10 digit driver used on the IND-1803. This driver card must have extra functions beyond mere overflow display.